Scores of civilians fled Raqqa on Friday ahead of an anticipated final push into the city by U.S.-backed fighters aiming to retake it from Islamic State militants.

Hundreds of civilians have been streaming out of Raqqa in the past few days from the remaining neighborhoods held by IS. They are taking advantage of a slowdown in the fighting by coalition troops meant to help civilians safely evacuate.

Residents say local IS fighters have been surrendering in recent weeks but still hold a few areas of the city, including the stadium and national hospital.

Many of those who escaped the city are malnourished after being trapped by the fighting for several months.

U.S.-backed fighters of the opposition Syrian Democratic Forces have been on the offensive in Raqqa since June 5 and have so far captured more than 80 percent of the city. Raqqa, on the banks of the Euphrates River, is the de facto capital of the Islamic State fighters.

Coalition officials say the IS militants are still holding some civilians captive to use as human shields.

Activists say more than 1,000 civilians have been killed in Raqqa since the battle to retake the city began in June. Nearly 270,000 people have fled Raqqa since April.